No, you can also have a mini roundabout, which is a white circle painted on the road. Maybe slightly raised but with no kerb so you can just drive over it. Yield to anybody in the junction and yield to the right (we drive on the left).

Very common in the UK instead of stop signs at intersections. Stop signs are only in rare places where a hedge or other environment prevents you from being able to see and yield to approaching traffic while approaching the junction. Even in that case there would never be a four way stop.